Fuel injectors are used to deliver fuel into a combustor wherein the fuel is burned to produce power in an engine. A variety of engines use fuel injectors including internal combustion engines, both spark ignited and diesel, gas turbine engines, pulse detonation engines, wave rotors, and the like. When hydrocarbon based fuels are exposed to high temperatures over a period of time, the fuel will thermally degrade or pyrolyse to form tars, lacquers, and coke. The degraded fuel will reduce the performance of the fuel injector and can eventually clog at least a portion of the fuel passages within the injector. To prevent thermal degradation, fuel injectors must be thermally isolated and/or have fuel flow velocities that are high enough to prevent excessive heat build up in the fuel. The present invention contemplates a novel and unobvious way to minimize thermal degradation of fuel in a fuel injector.